Vapor generator having a vapor heater with a novel outlet header



A\ ,1 g.-18, 1959 s. c. DEITRICK, JR 2,900,174

VAPOR GENERATOR HAVING A VAPOR HEATER WITH A NOVEL OUTLET HEADER Fi led May 13, 1954 E 9 f 34 5 IO fie z s z B a i d a [1 E l6 4 g i INVENTOR 'STAPLETON o. DEITRICK JR.

- BY QEE ATTQ EY United States Patent VAPOR GENERATOR HAVING A VAPO EATE WITH A NOVEL OUTLET HEADER Stapleton C. Deitrick, Jr., Summit, N.J., assignor to Combustion Engineering, Inc., New York, N. a corporation of Delaware v A Application May 13, 1954, Serial No. 429,483

2 Claims. (Cl. 257-241) This invention relates to vapor and more particularly steam generators for supplying superheated steam to the two inlets of a turbine and has particular relation to such a steam generator which has a steam heater particularly adapted to supply steam of equal temperatures to the two turbine inlets.

The steam turbines which form one of the major pieces of apparatus of a modern steam power plant are provided with two inlets which are supplied with superheated steam from a single steam generator. It is of course essential that the temperature and pressure of the steam delivered to each of these inlets be the same and prior to the present invention relatively complicated and expensive apparatus has been utilized for the accomplishment of this result including mixing chambers and the like.

The present invention represents an extremely simple yet highly satisfactory solution to this problem greatly reducing the complexity and cost of the required equipmeat.

It is an object of this invention to provide an improved steam generating organization for supplying superheated Figure 2 is a sectional view taken along line 22 of Fig. l and showing in detail the connection of the high temperature stage of the superheater with its outlet header;

Figure 3 is a sectional view taken along line 33 of Figure 2.

Referring now to the drawing wherein like reference characters are used throughout to designate like elements, the steam generator 10 which supplies high pressure, high temperature steam to turbine 12 comprises a furnace 14 lined with steam generating tubes 16 and fired with a suitable fuel by means of burners 18. The combustion gases generated by the burning of fuel in furnace 14 pass upward through the furnace, leaving the furnace at its upper end and passing horizontally through horizontal gas pass 21 and then downwardly through vertical gas pass 22 flowing serially over the heat exchange surfaces positioned in these gas passes including economizer 19 and air heater 21.

Adjacent the upper end of the furnace is positioned steam and water drum 24 which communicates with the upper ends of steam generating tubes 16 and from which depends downcomer 26. The lower end of the downcomer is connected into orifice drum 28 which is also connected with the lower end of steam generating tubes 16. Through the circulating system thus formed water from drum 28 flows downward through downcomer 26 and by means of circulating pump 30 is forced into drum 28 and upward throughsteam generating tubes 16 into drum 24 with the flow through the tubes being metered by orifices or restrictors (not disclosed) disposed in drum 28 and associated with the inlets of the tubes. In passing through these tubes a portion of this water is converted into steam with the steam and water mixture entering drum 24 being separated in the drum by means of suitable mechanism disposed therein.

In Order to raise the temperature of this saturated steam the steam generator is provided with a suitable heater or so-called superheater and in the illustrated Organization this superheater is divided into two sections or stages with the so-called low temperature stage 32 being disposed in gas pass 22 and the high temperature stage 34 being disposed in gas pass 21. Steam from drum 24 is conveyed through conduit 36 to low temperature stage 32 and from this stage the steam is conveyed through conduit 38 to high temperature stage 34 where its temperature is raised to the desired value with the steam entering outlet header means 40 after passing through this high temperature stage.

As is evident from the drawing the high temperature stage 34 of this superheater comprises a number of individual tubes 41 sinuously bent, as is common practice in superheater construction, with each tube disposed in a single plane with the planes being uniformly spaced across the width of gas pass 21 and being parallel with the flow of combustion gases through this gas pass. .The inlets of tubes 41 are connected with inlet header 42 and the outlets of these tubes are connected with outlet header means 40. This outlet header means is of special construction and is connected with the tubes of high temperature stage 34 in a particular manner in order to insure that the steam delivered to conduits 44 and 46 which respectively lead to the two inlets of turbine 12 is of the same temperature.

To this end the outlet header means comprises two elongated headers or conduits 48 and 50 disposed above the upper wall 52 of gas pass 21 and extending transversely of the gas pass with conduit 48 preferably being directly above conduit 50. These two conduits are positioned above the vertically extending outlet portions of tubes 41 and are joined at their central portion by connector 54 in order to provide for fluid flow from one of the conduits to the other. In order to insure that the temperature of the steam entering each of the conduits from tubes 41 is the same every other one of these tubes across the width of gas pass 21 is connected to a differend one of these conduits. With this arrangement the steam entering each of the conduits or headers 48 and 50 will be of substantially the same temperature due to the fact that the tubes connected to each of these conduits are equally spaced across the width of the gas pass and therefore swept by combustion gases of the same temperature and the same mass flow. Although in the organization disclosed alternate tubes 41 are connected to a different one of the conduits 4850 it will be understood that other arrangements for insuring equal steam temperatures in these two conduits are possible and practicable, as for example, alternate pairs of tubes may be connected to a different one of these two conduits.

The steam collected in conduit 48 is conveyed therefrom through conduit 44 to the left inlet of turbine 12, as viewed in Fig. 1, while the steam collected in conduit 50 is conveyed therefrom through conduit 46 to the right inlet of turbine 12. Positioned in each of these conduits are the usual valve means 56 which include the turbine stop and interceptor valves, the latter of which is automatically regulated to close in certain instances to prevent the turbine from running away.

Ordinarily there will be little or no steam flow from conduit 48 to conduit 50 or vice versa, through connector 54. However, should, for any reason, either of the valves 56 close, steam from the conduit associated with the closed valve will flow through connector 54 into the other conduit thereby preventing the overheating of the tubes associated with the first mentioned conduit which would otherwise occur.

While this inventive organization is here disclosed with relation to a superheater it is obviously equally applicable to a reheater organization where there are two inlets at the turbine for the reheated steam.

It is thus seen that with the present invention an extremely simple yet highly eflicient means is provided for supplying each of the two turbine inlets with steam of substantially the same temperature and at the same time insuring the superheater against damage resulting from the stoppage of steam flow in one of the conduits leading to one of these inlets.

While I have illustrated and described a preferred embodiment of my novel organization it is to be understood that such is merely illustrative and not restrictive and that variations and modifications may be made therein without departing from the spirit and scope of the invention. -I therefore do not wish to be limited to the precise details set forth but desire to avail myself of such changes as fall within the purview of my invention.

What I claim is:

1. In a vapor generator for generating superheated vapor, the combination of a passageway having a heating source that is nonuniform across the width of the gas pass, a vapor heater disposed in said gas passageway, said heater being comprised of a plurality of tubular panels each of which has its median plane disposed in parallel relation with the gas flow with these median planes of the several panels being parallel and with the panels being spaced across the width of the gas passageway, inlet header means connected with said panels to supply vapor thereto from a common source, a first outlet header disposed outwardly of said passageway and extending across the width thereof normal to said median planes, a second outlet header parallel and coextensive with the first and disposed close thereto in side by side relation, an unobstructed conduit separate from said panels interconnecting said headers, the outlets of substantially half of the panels being directly interconnected with a single of said headers, the outlets of the remaining panels being directly interconnected with the remaining header, these interconnections lying generally within the median plane of the respective panel, and the panels that are interconnected with one header being generally uniformly intercalated UNITED STATES PATENTS 1,908,733 Creel May 16, 1933 2,035,763 Robinson Mar. 31, 1936 2,715,019 Walter Aug. 9, 1955 2,797,900 Banker July 2, 1957 

